Comparative transcriptome analysis reveals significant differences in gene expression between pathogens of apple Glomerella leaf spot and apple bitter rot
Abstract Background: Apple Glomerella leaf spot (GLS) and apple bitter rot (ABR) are two devastating foliar and fruit diseases on apple. The different symptoms of GLS and ABR could be related to different transcriptome patterns. Thus, the objectives of this study were to compare the transcriptome profiles of Colletotrichum gloeosporioides, the common pathogen of GLS and ABR, and to evaluate the genes involvement on pathogenicity.Results: A relatively large difference was discovered between the GLS- and ABR-isolate, and quite a number of differential expression genes associated with pathogenicity were revealed. The DEGs between the GLS- and ABR-isolate were significantly enriched in GO terms of secondary metabolites, however the categories of degradation of various cell wall components did not. A number of genes associate with secondary metabolism were revealed. A total of 17 Cytochrome P450s (CYP), 11 of which were up-regulated while six were down-regulated, and five up-regulated methyltransferase genes were discovered. The genes associated with secretion of extracellular enzymes and melanin accumulation were up-regulated. Four genes associated with degradation of host cell wall, three genes involved in degradation of cellulose, and one gene involved in degradation of xylan were revealed and all up-regulated. In addition, genes involved in melanin synthesis, such as tyrosinase and glucosyltransferase, were highly up-regulated.Conclusions: The penetration ability, pathogenicity of GLS-isolate was greater than that ABR-isolate, which might be indicate that GLS-isolate originated from ABR-isolates by mutation. These results contributed to highlight the importance to investigate such DEGs between GLS- and ABR-isolate in depth.